A recent study by the U.S. International Trade Commission indicates that the counterfeiting of name brand goods is presently costing American businesses up to $8 billion in lost sales annually. In addition, the counterfeiting is effectively costing the work force some 131,000 jobs per year. Still more startling is the fact that the counterfeiting menace is increasing. The growth of counterfeiting, however, should be easy to understand when the huge profits obtainable by the counterfeiter on the sale of low quality, bogus goods at name brand prices are considered.
In order to combat the counterfeiting problem, technologies have been developed for placing an identifiable marker or tag on the name brand goods. Of course, the markers themselves must be made very difficult to counterfeit in order to be effective. Typically, the marking system is designed so that at least the cost of breaking the code and reproducing the marker or tag is prohibitive to the counterfeiter. However, on the other hand, the markers of the identifying system must be produced at a relatively low cost so as to make the concept economically feasible to the brand name manufacturer seeking to protect its products.
An example of a tagging or marking system is found in copending U.S. patent application Ser. No. 373,061, filed April 29, 1982, now U.S. Pat. No. 4,510,489 entitled "Surveillance System Having Magnetomechanical Marker" and assigned to Allied Corporation, the assignee of the present invention. The marker preferably includes an elongated, amorphous metal strip of ferromagnetic material adapted to be magnetically biased, and thereby armed to resonate mechanically, at a frequency within the frequency band of a magnetic interrogation field. Checking for authenticity is easily accomplished after exciting the strip with its natural resonant frequency by then electronically detecting the appropriate frequency.
One potential problem in providing an effective anti-counterfeiting system with this technology is the relatively limited number of available marker response frequencies. Thus, providing several companies with a relatively large number of coded markers to identify their different products while maintaining a distinctive response for each company and/or product has not been practical. In other words, in the past it was felt that the number of output codes from a reader was limited to the number of different marker ribbon frequencies available.
Furthermore, in the past it has not been feasible to place a visible coded indicia on the marker tag. The visible indicia would be useful in immediately indicating to the authorized person verifying the product that the proper output code is obtained. However, no effective system has been found heretofore to permit visible indicia display without jeopardizing the integrity of the system.
Thus, a need is identified for a simple and inexpensive means for disguising the marker response frequencies. Second, there is a need in the verification system wherein a visible code indicia may be attached to the product. Broadly, it is contemplated that by use of a programmable scanning unit and comparing the identifiable but disguised response signal of the marker to the visible indicia, the authentic product can be readily verified.